{ INFORMATICS.MCCME.RU
  Problem statement: http://informatics.mccme.ru/moodle/mod/statements/view3.php?chapterid=1562
  Verdict: Accepted
}
var a,r:longint; s:string;
begin
assign(input,'input.txt');
assign(output,'output.txt');
reset(input);
rewrite(output);
readln(S);
if s[2]='+' then begin
    r:=ord(s[1])+ord(s[3])-96;
end else
if s[2]='-' then begin
    r:=ord(s[1])-ord(s[3]);
end else begin
    r:=(ord(s[1])-48)*(ord(s[3])-48);
end;
write(r);
end.